It’s been nearly 40 years since the most innovative rock guitarist of the 1960s died in London at the age of 27, following an accidental barbiturate overdose that caused him to choke on his vomit. Sadly, Hendrix seemed already burned out before his passing on Sept. 18, 1970, the victim of an almost nonstop touring schedule, mounting financial pressures and an often perilous lifestyle that did not bode well for longevity. Indeed, less than two weeks before his death, he prophetically told a Danish concert audience: “I’ve been dead for a long time.”

The Seattle-born visionary, whose musical influence is almost as strong today as it was in his artistic heyday, completed only four studio albums and one official live album before his death. Dozens of posthumous releases have followed — a few memorable, most marginal, and some embarrassingly awful.

Enter the dozen-song “Valleys of Neptune,” in stores yesterday, ﻿which is being billed as “the much-talked-about debut appearance of 12 previously unreleased, fully realized Jimi Hendrix studio recordings.” The catch is in the wording, since such songs as “Stone Free,” “Fire” and “Red House” should be familiar to anyone who has even a passing familiarity with his repertoire. In fact, every song presented here has been available, some with different titles, for years, on legal or bootleg albums (or, in some cases, both).

The difference? Three of the nine songs were recorded with bassist Billy Cox, not original Jimi Hendrix Experience bassist Noel Redding, whom Cox replaced after Cox and Hendrix had recorded one live album with drummer Buddy Miles as the Band of Gypsys. ﻿The other nine songs on “Valleys” feature Redding but are alternate takes from the more familiar versions long cherished by Hendrix fans.

With a guitarist as bold and creative as Hendrix, the opportunity to hear new interpretations is welcome, and the slow-boiling version of the blues-drenched “Red House” is a treat (even if it fades out moments after Hendrix launches into a second solo).

“Valley’s” only real new peak, then, is the meticulously crafted “Lullaby for the Summer,” which features a chorus of cascading, multitracked guitars that hint at what might be a fruitful new direction for this doomed six-string dynamo.